etheeidae



(.No Model.) 2 Sheets-Sheet 1.

H. ETHERIDGE.

AUTOGRAPHIU TELEGRAPH. N0.445,715. Patented Feb. 3, 1891.

v 2 Sheets-Sheefn 2.

H. ET-HERIDG-E'. AUTOGRAPHIG TELEGRAPH.

Patented Feb. 3, 1891.

.IILEh -CEEFIUE UNITED STATES PATENT QFFICE,

HARRY ETHERIDGE, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO THE WRITINGTELEGRAPH COMPANY, OF NEW YORK, N. Y.

AUTOGRAPHIC TELEGRAPH.

SPECIFICATION forming part of Letters Patent No. 445,715, dated February3, 1891.

Application filed March 7, 1890. Serial No. 343,073- (No model.)

part of this specification, Figure l is a perspective View of a part ofmyimproved transmitter. Fig. 2 is a side view of the same. Fig. 3 is aplan view of Fig. 2, and Fig. 4 is a plan of the transmitter embodyingthe several features of my invention.

Referring to the drawings, 1 represents the top plate of thetransmitter, adapted to be held by an inclosing case. (Not shown.) A

.rod 2 depends from said top plate and supports the base 3. Secured tosaid base and arranged at right angles to each other, as shown, are tworeceptacles or holders 4, in which two series of steel spring-tongues 55 5", &c., are separately heldin a vertical position by aninsulating-cement 6. The springtongues 5, &c., are placed in line witheach other edge to edge, with asufficient space between them to avoidcontact. They are hardened and tempered, so as to readily return tonormal position after pressure thereon is rew leased. To the lower endsof these tongues a series of resistances 7 7 7", &c., are secured, asshown in Fig. 4,while their upper ends are provided with platinumcontacts 8.

Secured in the insulating-cement of each holder are two spring-strips 9,which carry a contact-bar 10, of brass, having its side next thespring-tongues arranged at an angle thereto, as shown in Figs. 3 and 4.These two contact-bars are each provided with a platinum strip orsurface 11, placed opposite the platinuin contacts of the springtongues, and, by reason of their spring-supports, can be brought intocontact with said tongues, each tongue making contact independently ofthe rest. A.

stylus-rod 12, screw-threaded on its lower end,

is screwed into the base 3, being held tightly in position by alock-nut. Its spring part 13 allows free movement of the upperend in anydirection. Aspring 14; is preferably employed to bring the stylus backto normal position. Said stylus-rod carries a pressure-block 15, securedthereto by two set-screws 16, the stylusrod passing through a hole insaid block. Two adjustable pressure-heads 17 are screwed to the block,and can be held tightly by locknuts 18 in whatever position they mayhave been adjusted. The faces of these pressureheads are hardened andpolished to secure a free and easy action when said heads press againstthe projections 19 on the contact-bars. These projections are likewisehardened and preferably terminate in a point, so as to present thesmallest possible surface to the pressure-heads. When the stylus is inits normal position, the pressure-heads are so adjusted that contact ismade with the projections 19, whereby any lost motion is prevented. Thepressure-heads are uninsulated, as well as the pressure-block, from thestylus-rod.

The advantages of a stylus-rod provided with uninsulated pressure headand block are i that it is much more cheaply and easily constructed, andpermits the attachment of hard ened-steel pressure-heads for preventing8o wear. hen the stylus is operated, the contact-bar is pressed againstthe tongues, making contact with all or a lesser number, according tothe extent of movement of the stylus, thus cutting in or out theresistances required 8 5 to regulate the movement of the receiving-pen.

Heretofore in autographic telegraph-transmitters the resistances havebeen arranged in series. This arrangement is objectionable, for anybreak of circuit at the points of contact means a break of the wholecircuit and oxidation at the contact-points. To overcome this objection,I'arrange the resistances as shown in the drawings. I employtwo seriesof resistances 7 '7 7 &c., and 20 20 &c., the former arranged inparallel are, the latter in series, and I combine these two in a mannerto avoid an electrical break in. the circuit. The objection to theseries system is to a considerable extent overcome by the re- 10osistauces 7 7i 7, &c., arranged in parallel are, for as the current isdistributed through several branches, which are broken when the contactsare separated, the possibility of oxidation at contact-points isproportionately reduced. The objection to the series system is, however,entirely overcome by combining with said resistances 7 7 a 7 &c.,another set of resistances arranged in series, independently considered,both sets of resistances being connected to the tongues. The resistance7 a is of the same resistance, measured in ohms, as resistance Theresistance 7 is less than 7 but is of the same resistance as 20, &c.,the resistances continuing to decrease-- that is to say, the resistancesare graded from a maximum resistance arranged farthest from the receiverto a minimum resistance of practically zero.

The operation is as follows: \Vhen the tongues are all out of contactwith the contact-bar, the current circulates in every branch, of courseproportionately to resistance. \Vhen, through the movement of thestylus, tongue 5 touches contact-bar 10, the resistance 7 is placed inparallel arc with re sistance 7, while the resistance 20, of equalresistance with 7 is practically electrically cut out, the amount ofcurrent still circulating in 20 being so extremely little as to bepractically disregarded. The resistance 20, therefore, prevents an opencircuit in 7 when 5 breaks contact with the contact-bar, balancing theresistance 7 then practically cut out, and so preventing an open circuitand consequent sparking. In other words, the resistance 2O offersanother and equivalent passage for the current the moment 7 is separatedfrom 7. The resistance 20 stands in the same relation to resistance 7 bthat 20 stands to 7 and so on throughout the remainder of thearrangement of resistances.

In the position of the stylus-rod shown in Fig. 4. the same makescontact with contactpieces and 26, and the circuits are then from thebatteries A and B through the mag nets of the receiver and by.conductors 40 and 41 to contacts 25 and 26 to stylus-rod 12, and thenceto ground by conductor 34, the transmitter being out out. When thestylus rod is pulled over to make contact with contact-piece 27 thecircuit is from battery A by conductor 42 to contact-piece 27 tostylus-rod 1.2., and thence to ground by wire 3%. The purpose of this isfully described in my ap plication, Serial No. 289,428, filed October20, 1888, and as it forms no part of this invention further descriptionhere is unnecessary. When the stylus-rod is being operated to Write, itis of course out of contact with contact-points 25, 26, and 27, and thecircuits are from batteries A and I3 through the magnets 30 of thereceiver, and by conductors 37 and 38 through the resistances of thetransmitter in manner as previously hereinbefore explained and by wiresand 36 to ground.

In Fig. 4 the opening in the top plate 1 for the passage of thestylus-rod is provided with notches 23 and 2t in two of its fourcorners. Contact-pieces 25 and 26, connected to receiver 30 by wires 40and 41, are arranged in notch 23, and contact-piece 27, connected withline 42 to connect with a ceutral-office switchboard, (not shown,) isarranged in notch 24:. These contact-pieces serve the same purpose, asdescribed in my application, Serial No. 289,428, filed October 29, 1888,and will need no further description here. I11 the construction shown inmy said former application, in'

which the said contact-pieces are placed in the corners of the squareopening, it would frequently happen if the operator was not very carefulin handling the stylus that the stylus-rod would come accidentally intocontact with said contact-pieces, and thus disturb the operation of theinstrument; but by notching or cutting out the corners of the squareopening, as shown in Figs. 1 and 4, I avoid this objection, and nomatter how careless the operator is in moving his stylus about he cannotaccidentally bring his stylus-rod into contact with said contact-pieces.By means of the notches I have not only moved the contact-pieces fartheraway from the center of the square opening than before, but haverendered them less easily accessible by the stylus-rod.

In Fig. 4,31 represents across-section of the receiving-stylus; 32, apart of the paper-feedreleasing mechanism, and 33 the contactpointsclosed by said mechanism; 34, the connection from transmitting-stylus toground; 35 and 36, the connections of the transmitter resistances withground, and 37 and 38 the wires connecting receiver to transmitter; butthese features constitute no part of this invention, being fullydescribed in my said application hereinbefore referred to, and anyfuller description in this application is unnecessary. I have arrangedthe resistances of the transmitter so that the last tongue to makecontact with the contact-bar controls thelowest resistance, and thisresistance is most directly connected with the receiver.

\Vhat I claim, and desire to secure by United States Letters Patent, is-

1. I11 an autographic telegraph, two series of contacts in which thecontacts of each series are separated from each other, two series ofresistances, each graded from a maximum to a minimum resistance, and twomovable contactbars, each arranged at an angle to its series ofcontacts, in combination with a stylus arranged when operated to pressagainst said contact-bars and press the latter against said contacts,substantially as described.

2.. In an autographic telegraph, two series of movable contacts in whichthe contacts of each series are arranged in line with but separated fromeach other and are movable at right angles to said line, two series ofresistances, each graded from a maximum to a IIO minimum resistance, andtwo movable con taotbars, each arranged at an angle to its se ries ofcontacts, in combination with a stylus arranged when operated to pressagainst said contact-bars.and press the latter against said contacts,substantially as described.

3. In an autographic telegraph, two series of flexible contacts in whichthe contacts of each series are separated from each other, and twomovable contact-bars, each carried by flexible supports and arranged atan angle to its series of contacts, in combination with a stylusarranged when operated to press againstsaid contact-bars and press thelatter against said contacts, substantially as de scribed.

4. In an autographic telegraph-tramsmitter, a series of contactsconnected to flexible supports, insulated from each other and arrangedin line with and movable at right angles to said line, in combinationwith a laterally-11lovable contact-bar arranged at an angle to saidcontacts and to press laterally against; the same, substantially asdescribed.

5. The combination, with a transmitting stylus provided with apressure-block, of two contact-bars carried by flexible supports andarranged to be moved by the operation of said stylus, substantially asdescribed.

6. The combination, with a transmittingstylus, of a pressure-blocksecured directly thereto and provided with a pressure-head, a movablecontact-bar provided with a projection co-operating with saidpressure-head, and a series of electrically separate contacts,substantially as described.

7. The combination, with a transmitting stylus, a top plate providedwith a notched opening and contacts in said notch arranged to co-operatewith the stylus-rod, of the stylus-rod arranged to pass through saidopening and a spring for returning the stylus-rod toits normal positionin said notch, substantially as described.

8. The combination, with a transmittingstylus and a top plate providedwith a notched opening, of contacts in said notch arranged to cooperatewith the stylus-rod, and a stylus-rod arranged to pass through saidopening and to be pressed against said contacts in said notch,substantially as described.

9. In an autographic telegraph-transmitter, the combination, with twosets of contacts and connecting means for electrically connecting thecontacts of each set of two sets of resistances, each set arranged toact in parallel arc, and a stylus-rod co-operating with said connectingmeans, substantially as described.

10. In an autographic telegraph-transmitter, the combination, with twosets of contacts and connecting means for electrically connecting thecontacts, of two sets of resistances, each set arranged to act inparallel arc, and two sets of resistances, each set arranged in series,substantially as described.

11. In an autographic telegraph-transmitter, two sets of resistancesconnected to contacts and each set arranged to act in paral lel arc, incombination with two sets of resistances, each set arranged in series,substantially as described.

12. In an autographic telegraph-transmitter, the combination, with twosets of contacts, of two sets of graded resistances, each set arrangedto act in parallel arc and graded from a maximum to a minimumresistance, substantially as described.

13. In an autographic telegraph-transmitter, the combination, with twosets of contacts, of two sets of graded resistances, each set arrangedto act in parallel arc, and two sets of graded resistances, each setarranged in series, substantially as described.

14. In an autographic telegraph, the combination, with the receiver andtransmitter, of two sets of contacts and two sets of graded resistances,each set arranged to act in parallel arc, the lowest resistances of eachset arranged nearest the receiver, substantially as described.

1 5. The combination, with the transmittingstylus provided with anuninsulated pressureblock and a contact-bar co-operating therewith, of aset' of contacts and a set of graded resistances, arranged with thelowest resistance next to the receiver, said contact-bar arranged tomake contact with the contact of least resistance last, substantially asdescribed.

In testimony that I claim the foregoing as my invention Ihave signed myname, in presence of two witnesses, this 24th day of February, 1890.

HARRY ETHERIDGE.

Witnessesi F. V. MOMULLEN, JAMES H. PORTE.

